Does anyone know if type 1 diabetics are allowed to scuba dive at CN?

My husband and I were booked for a dive excursion on our honeymoon through one of the cruise lines and they would not let my husband dive because he is insulin dependent. Since then we have spoken to a PADI shop and were told that he could difinately get certified as a diver, but must have his doctor sign a PADI authorization form. His doctor has completed the forms for PADI, but we haven't yet gone through the certification process.

So, long story short... would Couples allow him to dive if we provide them with the documentation that PADI requires?